The SLX M677 Hollow Tech II 10 Speed MTB 38/24 Chainset from Shimano is a tough & aggressive all-mountain chainset that is also lightweight & excellent value for your money. It features hollow forged crank arms which are both lightweight & rigid, whilst keeping the incredibly strength & durability. The Hollowtech II integrated bottom bracket design uses a wide bearing placement with a large axle diameter for increased stiffness, efficiency & added durability. The chainrings are HG-X 10-speed Dyna-Sys plus with patented single spike pins that gives smooth & fast gear shifts, even under load. Available in Black with 170mm or 175mm crank lengths.